6 January 1995 Nondestructive testing for identifying poor-quality onions
Author Affiliations +
Proceedings Volume 2345, Optics in Agriculture, Forestry, and Biological Processing; (1995) https://doi.org/10.1117/12.198893
Event: Photonics for Industrial Applications, 1994, Boston, MA, United States
Methods of nondestructively examining Granex type sweet onions are needed to insure that only good quality onions are shipped at harvest and to avoid putting infected onions in controlled atmosphere (CA) storage where they occupy valuable space and can ruin surrounding onions. A Toshiba TCT 20Ax tomographic scanner operated in the line scan mode and an incandescent light box were used to evaluate the potential for detecting infected onions nondestructively. A study (CA storage study) involving 200 onions, 100 harvested early and 100 harvested late, one half destructively inspected before the remaining half were placed into CA storage was initiated May 1994. All onions were line scanned and scored with the light box before CA storage and those in CA storage were line (will be) scanned and optical scored on retrieval from the storage. An additional study (Disease storage study) involving 40 onions, late harvest, stored at 25C, 60% rh for three weeks with line scanning as above on a weekly interval. After the third week these fruit were assayed for visual damage and for decay organisms. Results from the incandescent light box scoring were not encouraging. From both studies the number of defects, average defect size and the difference image intensity as determined from line scanning were the major contributing parameters to a discriminant analyses model predicting about 70% or better accuracy.
© (1995) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Ernest William Tollner, Yen-Con Hung, B. W Maw, D. R. Sumner, R. D. Gitaitis, "Nondestructive testing for identifying poor-quality onions", Proc. SPIE 2345, Optics in Agriculture, Forestry, and Biological Processing, (6 January 1995); doi: 10.1117/12.198893; https://doi.org/10.1117/12.198893

Back to Top